Method of manufacturing three-dimensionally formed foods

ABSTRACT

In a method of manufacturing three-dimensionally formed foods which comprises the step of continuously processing food material into a three-dimensional form by using a drum-type forming machine in which the forming surface of the forming blocks is release treated, the method comprises the steps of forming the food material by filling it into the forming blocks, and separating the formed food material (formed products) from the drum surface by jetting compressed air thereto. The method comprises the further step of spraying water, steam or hot water, spreading grain powder, or applying edible oil or fat, onto the forming blocks prior to filling the food material into the forming blocks. The method permits the continuous mass production of three-dimensionally formed foods with stable quality.

TECHNICAL FIELD

The present invention relates to a method of manufacturingthree-dimensionally formed foods.

BACKGROUND ART

Manufacturing of three-dimensionally formed foods having an unevensurface has been performed by a press method or by putting a decorationon a surface of a food once formed into a plate. These methods, however,have low productivity and are not suitable for continuous massproduction.

On the other hand, a method using a drum type forming machine has beenknown as a method of permitting continuous mass production. In thismethod, formed foods extruded out of the molds, i.e., the forming blocksare separated from the forming machine by means of extendedly disposedpiano wires and cut belts. Consequently, every separated food results inthe form of a plate due to a piano wire, even if the forming block isformed to give an uneven surface. It is therefore impossible tomanufacture three-dimensionally formed foods having an uneven surfacewith the use of such a drum type forming machine.

Nowadays, there is a great demand for foods in a wide variety of forms,attributable to the diversification of the needs from consumers;therefore, a technology is much expected to be developed which allowscontinuous mass production of three-dimensionally formed foods to berealizable in various forms with stable quality.

DISCLOSURE OF THE INVENTION

The present invention is to solve such problems, and to provide a methodof continuously mass-producing three-dimensionally formed foods withstable quality.

More particularly, the invention is to provide a method of manufacturingthree-dimensionally formed foods with the use of a drum-type formingmachine.

Having strived to solve these problems, the present inventors have cometo find that when food materials are continuously processed into athree-dimensional form using a drum-type forming machine with formingblocks whose forming surface is release treated, the occurrence rate ofdefectively formed products can be unexpectedly reduced by separatingthe food material formed with the forming blocks (formed products) fromthe surface of the drum by jetting compressed air thereto; and that theoccurrence rate of defectively formed products can be also reduced byprespraying water, steam or hot water, prespreading grain powder orpreapplying edible oil or fat, to the forming surface of the formingblocks, depending on the kind of the food material, in addition toseparating the formed products in such a manner as mentioned above,prior to filling the food material therein, whereby three-dimensionallyformed foods can be continuously manufactured with stable quality; andthey have completed the present invention based on the above findings.

Thus, the present invention relates to (a) a method of manufacturingthree-dimensionally formed foods comprising the step of continuouslyprocessing food material into a three-dimensional form by means of adrum-type forming machine with forming blocks whose forming surface isrelease treated, the method comprising the steps of forming the foodmaterial by filling it into the respective forming blocks, andseparating the formed food material (formed product) from the drumsurface by jetting compressed air thereto; and (b). The manufacturingmethod comprises the further steps of, prior to filling the foodmaterialinto the forming blocks, spraying water, steam or hot water, spreadinggrain powder, or applying edible oil or fat to the forming surface ofthe forming blocks.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 and 3 illustrate outlines of the method of manufacturingthree-dimensionally formed foods by means of a drum-type formingmachine.

FIGS. 2(a) and 2(b) illustrate a release treated forming block.

DESCRIPTION OF THE INVENTION

The present invention will now be described in more detail, as follows.

As a drum-type forming machine to be used in the manufacturing method ofthis invention in respect of which the forming surface of its formingblocks is release treated can be utilized a conventionally knowndrum-type forming machine in which the forming surface of its formingblocks is release treated, without being subjected to any specificrestrictions, as far as it can attain the objects of the presentinvention.

In connection with the drum-type forming machine, explanation will bemade referring to FIG. 1. It includes a rotating drum-type formingmachine body (1) including forming blocks having a hopper for foodmaterial to be formed (i .e., to be processed into a three-dimensionalform) (2) and a belt conveyor (3) for conveying formed products as itsprincipal parts.

The drum-type forming machine body is provided with more than twoforming blocks (not all of the forming blocks are shown in FIG. 1), andtheir forming surfaces are raised or lowered with the rotation of thedrum. The movement of the forming blocks will be described referring toa specific block (4) as follows; First, this forming block, when itsforming surface is-lowered to the limit, receives food material from thefood material hopper and the is filled material therein. With therotation of the drum, the bottom surface of the forming block (formingsurface) is raised (4' position) to extrude the food material filledtherein and formed (the formed product), and the forming surface is thenraised to the limit (4" position). The formed product (5) is thenseparated from (the surface (6) of the drum to be transferred onto abelt conveyor. With a further rotation of the drum, the forming block,when its forming surface is lowered to the limit (4 position), receivefood material again and goes into the following cycle of its movement.

In FIG. 2(a), a forming block (4) is shown with an example of themechanism for raising and lowering its bottom surface.

FIG. 2(b) is to illustrate a release treatment on the forming surface ofa forming block.

The forming surface of the bottom part (4a) of the forming block is in ashape so as to give the formed product a spherical or any other shape,or an uneven surface and/or a patterned surface by blanking. The releasetreatment of the forming surface means a treatment to make the formedproducts easily releasable from the forming blocks. For that purpose,the forming surfaces may be coated with teflon, ceramic, silicon, or thelike, regardless of the kind, but the most preferred one is a ceramictreatment. The thickness of the coating and the method of coating arenot particularly limited. In the case of a teflon treatment, forexample, only coating with fluoroplastic as solid membrane lubricantwill suffice, while the method of coating, the thickness of the coating,and the like are not particularly defined. In FIG. 2, 4b denotes arelease treated surface layer.

Food materials to be processed into a certain form by the method ofmanufacturing three-dimensionally formed foods according to the presentinvention include meats of animals, birds and whales, fishes andshellfishes, eggs, grains, corms and the processed foods thereof, andthey are not limited to specific kinds, specific thermal or non-thermaltreatment, and specific methods of processing. Three-dimensional foodsaccording to the present invention designate foods having a certain formother than flat, i.e., those of a spherical shape or those having anuneven surface and/or a patterned surface by blanking. Examples of suchforms include human and animal faces, plants, fruits, flowers and comiccharacters.

Separating the food material formed into an above-described form from anabove-described food material by means of the forming blocks (formedproducts) from (the surface of) the drum according to a conventionalmethod results in a high occurrence rate of defectively formed products.

According to the present invention, the occurrence rate of defectivelyformed products is unexpectedly decreased by performing the separationof formed products from the drum surface by -jetting compressed airthereto. This is illustrated in FIG. 1. In the figure, a compressed airnozzle (7) is disposed in such a direction that the formed products canbe easily separated. According to the present invention, compressed air,for example, air compressed by means of a compressor, is jetted from anozzle having a rectangular or circular cross-section.

In order to decrease the occurrence rate of defectively formed products,it can be additionally employed to spray water, steam or hot water, tospread grain powder, or to apply edible oil or fat, to the formingblocks, prior to filling food material therein.

In FIG. 1, a case of spraying water is shown as an example. The watercontained in a water tank(8) is sprayed through a water spraying nozzle(9). In FIG. 3, a case of spreading grain powder (11) is shown as anexample, instead of spraying water as shown in FIG. 1. The grain powdercontained in a grain powder hopper (10) is spread through the hopper(10) at a desired time.

Apparently, it is after separating the formed products but prior tofilling food material for the following cycle that water, steam or hotwater is sprayed, grain powder is spreaded, or edible oil or fat isapplied, to the forming blocks, considering the objects of theseoperations.

The grain powder to be used according to the present invention may beany powder which can be utilized as so-called dusting powder, such aswheat flour, rice powder and various kinds of starch. And, edible oil orfat may be vegetable oil, such as salad oil, and animal fat, and theseoils and fats may contain food additives, such as detergent.

The food material formed according to the manufacturing method of thepresent invention (formed products) may, if solidification of theirshape is required, be solidified in their form by drying, heating suchas deep frying in heated oil, or in any other appropriate manners.Moreover, when food materials are required to be cooked as they are rawand therefore the formed products thereof cannot be eaten as they are,it is of course possible, if appropriate, to make the heating forsolidifying their shape function as the heating for cooking. In the caseof deep frying, the formed products can be deep fried by throwing themdirectly into heated oil, not by way of a belt conveyor.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be further described by way of the followingtest examples (examples and comparative examples).

TEST EXAMPLE 1

Using mashed potatoes as a food materials to be formed, formability,i.e., probability of being processed into a desired three-dimensionalform, was determined by means of a drum-type forming machine havingforming blocks made of ordinary stainless steel or those blockssurface-treated with teflon, silicon or ceramic. Separation of theformed products from the forming blocks was by natural dropping, whilethe shapes of the formed products were solidified by deep frying inheated oil.

The results are shown in Table 1.

                  TABLE 1                                                         ______________________________________                                                      No. of defective                                                              products/No. of total                                                                        Deficiency                                       Forming blocks                                                                              formed products                                                                              rate (%)                                         ______________________________________                                        Made of stainless steel                                                                     192/200        99.0                                             Treated with teflon                                                                         149/200        74.5                                             Treated with silicon                                                                        151/200        75.5                                             Treated with ceramic                                                                         61/200        30.5                                             ______________________________________                                    

As shown in Table 1, in the case of using the forming blocks made ofstainless steel, the formed products did not successfully drop onto thebelt conveyor due to insuficient separation, and almost no completelyformed products were obtained. In the case of using the forming blockstreated with teflon or silicon, as many as about 75% of the total formedproducts were defectively formed. In the case of using forming blockstreated with ceramic, the occurrence rate of defectively formed productsas noted above was considerably reduced to about 30%; however, it needsto be further reduced.

TEST EXAMPLE 2

TEST EXAMPLE 1 was repeated so far as forming blocks made of stainlesssteel and those blocks treated with ceramic, but separation of theformed products was carried out by means of compressed air. The resultsare shown in Table 2.

                  TABLE 2                                                         ______________________________________                                                      No. of defective                                                              products/No. of total                                                                         Deficiency                                      Separation    formed products rate (%)                                        ______________________________________                                        Forming blocks                                                                              195/200         97.5                                            made of                                                                       stainless steel +                                                             compressed air                                                                Forming blocks                                                                               1/200           0.5                                            treated with ceramic +                                                        compressed air                                                                ______________________________________                                    

As shown in Table 2, for the forming blocks made of stainless steel,most of the formed products were partially defective products ordefective ones due to unsuccessful dropping onto the conveyor belt(defectively formed products); however, for the forming blocks treatedwith ceramic, the occurrence rate of partially defective products anddefective ones due to unsuccessful dropping onto the conveyor belt wasreduced to approximately 0%.

TEST EXAMPLE 3

Using meat material, formability was determined in the above-mentionedmanner. The shapes of the formed products were solidified by heatingwith heated stream, which functioned as heating for cooking.

The results are shown in Table 3.

                  TABLE 3                                                         ______________________________________                                                      No. of defective                                                              products/No. of total                                                                         Deficiency                                      Separation    formed products rate (%)                                        ______________________________________                                        Forming blocks                                                                              198/200         99.0                                            made of                                                                       stainless steel +                                                             compressed air                                                                Forming blocks                                                                              160/200         80.0                                            treated with ceramic +                                                        compressed air                                                                Forming blocks                                                                              160/200         80.0                                            made of stainless                                                             steel + compressed                                                            air + water                                                                   Forming blocks                                                                               2/200           1.0                                            treated with ceramic +                                                        compressed air +                                                              water                                                                         ______________________________________                                    

As shown in Table 3, in the bases of using the forming blocks made ofstainless steel and the forming blocks treated with ceramic respectivelyin combination with compressed air, for the forming blocks made ofstainless steel, almost all formed products were partially defectiveones and defective ones due to unsuccessful dropping onto a beltconveyor, while even for the forming blocks treated with ceramic, theoccurrence rate of the defectively formed products was approximately80%. Moreover, in the cases of using the forming blocks made ofstainless steel and the forming blocks treated with ceramic respectivelyin combination with compressed air and water spraying, the occurrencerate of the defectively formed products was 80% for the forming blocksmade of stainless steel, while the rate was virtually 0% for the formingblocks treated with ceramic. Even with meat material which is difficultto be separated from a forming block, if water spraying is used inaddition to employing a forming block treated with ceramic incombination with compressed air, it is thus possible to attain nearly100% of formability.

TEST EXAMPLE 4

As shown in Table 3, starch is applied through the grain powder hopper10 onto a forming block 4 treated with teflon, or salad oil is spreadedover the surface of the forming block 4. After filling food material tobe formed through the food material hopper 2 in the forming block 4equipped in the drum-type forming machine body 1, the drum is rotated.When the forming block 4 passes the lowest point of the drum-typeforming machine body 1, the formed food material (formed product) 5starts to be extruded out of the forming block 4. Compressed air iscontinuously or intermittently jetted through the nozzle 7 to the formedmaterial to separate the formed product 5 from the forming block 4. Theseparated formed product 5 is then conveyed by means of the conveyorbelt 3.

Mashed potatoes were thus formed.

In the each of respective cases for separating shown in Table 4, 200formed products were manufactured. The formed mashed potatoes weresolidified in their shape by deep frying in heated oil.

The results are shown in Table 4.

                  TABLE 4                                                         ______________________________________                                                      No. of defective                                                              products/No. of total                                                                        Deficiency                                       Separation    formed products                                                                              rate (%)                                         ______________________________________                                        Forming blocks                                                                              200/200          100                                            made of                                                                       stainless steel                                                               Forming blocks                                                                              132/200          66                                             made of stainless                                                             steel + starch                                                                Forming blocks                                                                               0/200            0                                             treated with teflon +                                                         starch                                                                        Forming blocks                                                                              122/200          61                                             made of stainless                                                             steel + salad oil                                                             Forming blocks                                                                               0/200            0                                             treated with                                                                  teflon +                                                                      salad oil                                                                     ______________________________________                                    

As shown in Table 4, in the test according to the method of the presentinvention, no defective products (defectively formed products) werefound among the formed products.

INDUSTRIAL APPLICABILITY

According to the present invention, three-dimensionally formed foodssuch as those having an uneven surface can be continuously mass producedwithout producing defective products (defectively formed products) bymeans of a drum-type forming machine.

We claim:
 1. In a method of manufacturing three-dimensionally formed foods which comprises the step of continuously processing food material into a three-dimensional form by means of a drum-type forming machine with forming blocks whose forming surface is release treated, the improvement comprises the steps of: forming the food material by filing the food material into the forming blocks; extruding the formed food material from the forming blocks thereby raising the formed food material above a surface of the drum-type forming machine; and separating the formed food material from the surface of the drum-type forming machine by jetting compressed air thereto.
 2. The method according to claim 1, further comprising the step of: spraying water, steam or hot water, spreading grain powder, or applying edible oil or fat onto the forming surface of the forming blocks, prior to filling said food material in said forming blocks. 